How to adjust valves on a chevy smallblock

There are a several methods for a valve adjustment on a chevy small block engine.
Everyone seems to have a valve adjustment method they are most comfortable with and some of
them will work well, but some are an inaccurate valve adjustment method. Even GM recommends doing the valve
adjustment while the engine is running, which I won't teach you because it makes a tremendous mess.

You are going to learn how to do the valve adjustment, or more
appropriately, adjust the lash or clearance between the rocker arms and the head
of the valve stems using a method that will work for all 4 stroke
internal combustion engines. The only difference between engine makes and models would be the details such as
the number of turns after you have reached a zero lash, or in the case of solid
lifters, the lash setting.

I did it Myself!

With Tools and Instructionfrom Seasoned Pros.

First consider that there is a relationship between the high
position on each cam lobe for each cylinder respective of which stroke the
cylinder happens to be in. We are going to adjust each valve at a time relative
to the position of its peer valve ( or cam lobe ), either the intake or exhaust. This method insures the cam lobe for the valve you are adjusting is directly opposite the valve lifter and there is no measure of lift acting on the valve train components
.

To do the valve adjustment you will need to crank the engine over in the same direction it would turn if it were
running. If the engine is not in the vehicle you can turn the flywheel, or if it
is in the vehicle you can use a remote starter button.

You will do the intake valve adjustment as the exhaust valve is just
opening and you do the exhaust valve adjustment as the intake valve is almost closed.
You might need to say that quite a few times to memorize it.

Here are step by step instructions:

Remove the valve cover.

Identify the number one cylinder. See the page on Firing Order on the menu to the right if you are not sure which cylinder is number one.

Turn the engine over until you see the number one cylinder
exhaust valve rocker arm JUST START to move from the closed position to open. You may need
to turn the motor over a couple of times to reach this point, but do not turn
any further.

Locate the intake valve.

Loosen the rocker arm adjustment nut until you feel some obvious
lash or clearance in the adjustment.

Using the thumb and index finger of one hand, grasp the intake
push rod below the rocker arm, and rotate it back and forth (clock-wise and counter
clock-wise successively to be sure there is no remaining pressure on the push
rod from the rocker arm as you loosen the rocker arm adjusting nut.

Using the other hand, while continuously performing step 6, with
a 5/8 socket and ratchet, tighten the rocker arm adjustment nut slowly until you
feel a resistance of motion on the push rod.

This will be the zero lash adjustment point. For hydraulic
lifters, tighten the rocker arm adjustment nut 3/4 of a turn. For solid lifters,
back off the rocker arm adjustment nut until your feeler gauge just fits under
the contact point between the valve stem and the rocker arm. Fine tune the
adjustment by checking it with a feeler gauge just slightly thicker than the
preferred clearance to be sure the clearance is not greater than it should be.
If the larger feeler gauge will fit, it needs to be re-adjusted. A lash
tolerance of 1-2 thousandths of an inch in the valve adjustment for solid
lifters would be acceptable since it may be difficult for someone who is
in-experienced to be more precise than that.

Turn the engine over until the intake valve opens and then is
almost closed.

On the exhaust valve, repeat steps 5 through 8 for the exhaust
valve adjustment.

Repeat this procedure for each cylinder. Be sure to do each
cylinder sequentially, either following the firing order, following the
cylinders numerically, or in the case of a V8 doing one side of the engine at a
time. I prefer to do one side of the engine at a time.